Electric terminal post.



A. G. WILSON.

ELECTRIC TERMINAL POST;

APPLICATION FILED oomo, 1907.

w'i/Wowo wvbqr Patented Dee 8,1908.

"State of Pennsylvania, have UNITED sTAr is PATENT OFFICE.

ASBURY G. WILSON, OF WILKINSBURG, PENNSYLVANIA, ASSIGNOR TO THE UNION SWITOH 8i SIGNAL COMPANY, OF SWISSVQLE, PENNSYLVANIA,;A CORPORATION OF PENNSYLVANIA.

ELECTRIC TERMINAL POST.

. Specification of Letters Patent Patented Dec. 8, 1908.

Application filed October 10, 1907. Serial N 0. 396,723.

Be it known that I, AsBURY G. WILSON, a citizen of the United States, residing at VVilkinsburg, in the county of Allegheny and invented certain new and useful Improvements in Electric Terminal Posts, of which the following is aspecification.

My invention relates to electric terminal posts, and by an electric terminal post I mean a post contained in electric circuit and carrying a carbon contact against which a movable contact is pressed and withdrawn at intervals.

I will describe an electric terminal post embodying my invention and then point out the novel features. thereof in claim.

In the accompanying drawing Figures 1 and l are end and side elevations of an elec- I especially amount of wear which tric terminal post embodying my invention.

Similar letters of reference designate corresponding parts in both figures.

Heretofore in electric terminal posts, and those used in relays forrailway switch and signal work and which comprise a carbonor gra hite contact against which a moving metal 10 or othercontact was pressed and withdrawn at intervals, solder was employed .to hold the carbon or raphite contact in the socket provided for 1t in the post, and the moving contact engaged the projecting end of the carbon or graphite. After some use of a terminal post, the moving metallic contact constantly engaging the end of the carbon or graphite piece, produced an not only impaired the efliciency of the post, but 1n some cases caused the moving contact to be held against the carbon or graphite and when it should have moved away from it. With thecarbon' or graphite-contact soldered in its socket, it was dlfiicultto change the position of the carbon or graphite to avoid having the moving contact engaging the worn part. In my invention, the carbon or graphite contact is mechanically held in the post, and the mov ing contact is brought into engagement with the side surface of the carbon or graphite contact as distinguished from the 'end surface. The mechanical holding of the carbon or graphite contact permits of the contact being changed or turned so as to-present new surfaces with which the moving contact can engage, and the cylindrical surface affords more surface which may be used than is af-v and forming part of an' for drawing the jaws The post may be of any desired shape according to the purpose for which it is intended. In any event 1t is provided with a pair of 6 I s rin 'aws a a each of which is formed or provided with a curved face a to receive a carbon or graphite contact B. The contact B is held between the spring jaws a, a and Y I as shown in the drawing some means is pref- 7 erably provided, as, for example, a screw 11 a, 0, together thereby securely clamping the contact B between them. 'As shown in the drawing the post is providedwith an enlarged end portion, the 7 jaws a, a being formed by cutting a groove a therein. As shown the jaws a, a, do not entirely surround the carbon contact B, and thus a portion of the peripheral surface of the carbon is left exposed between the ends of 8 the jaws. I I

' C designates the moving contact which is moved by some suitable means into-and ,out of engagement with the exposed surface ofthe contact B. i

My invention may be used to considerable advantage in relays for railway signal and switch purposes, for in such relays the moving contact C which is generally a spring contact, is carried by the armature, and the spring of the contact is depended upon in some measure to move the contact away from the carbon contact B when the armatu're is no longer attracted by its magnet. Obviously if the moving contact wears the carbon contact to any degree (which is often the case) theamount of spring available to move the contact 0 away from the contact B is lessened. The armature is also permitted to move closer to its core by reason of the- Wear on the contact B. In some cases it'has been found that where the carbon contact has become worn, and the anmature brought closer to its core than was originally intended, residual magnetism would hold the 1 armature a ainst the core and thus the contact C won (1 be held against the contact B when it should have moved away. Also the solder used for securing the carbon in its socket required acid to make it efl'ecti ve, and 1 it has been found that this acid in time leaks out onto the moving contact and corrodes it. By my invention as soon as the carbon contact becomes worn the screw a is loosened so that the carbon may be turned to present a new surface with which the moving contact engages.

Having thus described my invention, what I claim as new is An electric terminal post comprising a pair of spring jaws, a cylindrical carbon contact partially inclosed bysaid jaws to leave a porits peripheral surface exposed, and

tion of eoaeee mechanical means for adjustably holding the contact betweenthe spring jawe, combined name to this s ecification in the prese 'u witnesses.

' two subscribe ASBURY "iv-in said expo Witnesses:

T. G. SCHUEDER, l\ H. PATENALL.

1 have be sad 

